pH/ Hard water

This is a discussion on pH/ Hard water within the Freshwater Aquarium Equipment forums, part of the Beginner Freshwater Aquarium category; -->
What's the best way to take hard water ( high GH and low KH ) with a pH of 8-8.5 and make it Acid/Soft ...

RO/DI water will lack the the dissolved minerals ... lowering hardness ... but will lack the buffers that prevent pH swings. If your looking to lower hardness / pH for fish ... most aquarium fish will adapt to your tank's natural pH ... usually your tap pH if that's what's used during water changes. You can also add Driftwood / peat to a tank to lower pH.

Keeping a stable pH is much more important than trying to get a 6.8 pH because online sources say that is the optimum pH for a particular fish. Chances are that fish will do just as well in a 7.4 pH tank.

I find and always suggest that it is easier for the hobbyist and better for the fish all round, if you choose the fish that best suit your water parameters, rather than try to change the parameters to suit the fish.

The kH is 11 and the gH is 7 with the pH approaching 9 ( by our test kit, the fish store test = 7.8 pH ) !

if your test and that of the store varies that much, you may want to try for a third reading, find another store or something. a difference of 1.2 is a huge difference in pH and suggests that there is something wrong with one of the tests.

The kH is 11 and the gH is 7 with the pH approaching 9 ( by our test kit, the fish store test = 7.8 pH ) !

I am wondering if you got the kh and gh numbers mixed? With a gh of 7 your water is actually soft, the kh I believe would be considered to be on the higher side which would keep the ph from decreasing as much in the tank. That is if I am understanding everything correctly, still learning alot that comes with the fun obsession, ummm I mean hobby. For your ph is this the number from the tap or from the tank? Also what is your reasoning behind wanting to lower the numbers, I am assuming because of the type of fish you are or are wanting to keep?

The pH is from the tap But after letting it sit for 48hrs. it now reads the same as the tank water. This is what some of the books said to do, allow the tap water to sit for 48hrs. before doing a water change and I can see why.By the way we have well water.According to the test kit info. the kH is at the lower end of normal and the gH is slightly above norm by 1 degree.

The pH is from the tap But after letting it sit for 48hrs. it now reads the same as the tank water. This is what some of the books said to do, allow the tap water to sit for 48hrs. before doing a water change and I can see why.By the way we have well water.According to the test kit info. the kH is at the lower end of normal and the gH is slightly above norm by 1 degree.

Perhaps I can explain this. Tap water usually contains some CO2 (carbon dioxide). CO2 causes carbonic acid which lowers pH. So when you measure the tap water pH right out of the tap, if there is a lot of CO2 in the water it will be lower than the actual pH. Letting tap water sit overnight before testing allows the CO2 to dissipate out, as it naturally will; or you can shake the water briskly. The pH will then be "true" as it will be the actual pH of the water.

When it comes to water changes, there is no need to let water sit out. However, if the variation between tank and tap is significant in pH and hardness, a smaller volume of water might be preferable to doing a massive water change.

The pH is linked to hardness, but can be high even with low hardness depending upon everything that is in the water. At this point, we should review everything, because I am a bit confused by the numbers being tossed about in this thread.

First, what is the hardness (GH and KH) and pH of your source water out of the tap [using the pH after the water sits]?
Second, what is the pH of the tank water? Presumably hardness will be the same, unless you have calcareous substances in the tank to raise it.
Third, what fish species do you want to keep?

There are easy ways to lower hardness and pH [the two must occur together in most cases, though not always] if that is necessary. The above answers will tell us this.

i read some where that one of the easiest and cheapest ways was to do a 20% water change with pure H2O like rain water or buying RO (reverse osmosis water)
instead of buying a RO device that run around $50-60

and i believe that the hardness i was suffering from was because of heavy metals like copper and calcium in my pipes from the water i was using in my tank because i always had a low ph and very high hardness